read configuration file

vendor/github.com/pyke369/golang-support/bslab/bslab.go

@@ -0,0 +1,89 @@
+package bslab
+
+import "sync/atomic"
+
+type slab struct {
+	queue                 chan []byte
+	get, put, alloc, lost int64
+}
+
+var (
+	slabs = map[int]*slab{}
+)
+
+func init() {
+	slabs[0] = &slab{}
+	for size := uint(9); size <= 26; size++ {
+		slabs[1<<size] = &slab{queue: make(chan []byte, 1024)}
+	}
+}
+
+func Stats() (info map[int][5]int64) {
+	info = map[int][5]int64{}
+	for size, slab := range slabs {
+		info[size] = [5]int64{slab.get, slab.put, slab.alloc, slab.lost, int64(len(slab.queue))}
+	}
+	return info
+}
+
+func Get(size int, item []byte) []byte {
+	if size <= 0 {
+		return nil
+	}
+	if item != nil {
+		if cap(item) >= size {
+			return item[:0]
+		}
+		Put(item)
+	}
+	bits, power := uint(0), uint(0)
+	if size&(size-1) == 0 {
+		power = 1
+	}
+	for size != 0 {
+		size >>= 1
+		bits++
+	}
+	size = 1 << (bits - power)
+	if slab, ok := slabs[size]; ok {
+		atomic.AddInt64(&(slab.get), 1)
+		select {
+		case item := <-slab.queue:
+			return item[:0]
+		default:
+			atomic.AddInt64(&(slab.alloc), 1)
+			return make([]byte, 0, size)
+		}
+	}
+	atomic.AddInt64(&(slabs[0].get), 1)
+	atomic.AddInt64(&(slabs[0].alloc), int64(size))
+	return make([]byte, 0, size)
+}
+
+func Put(item []byte) {
+	if item == nil || cap(item) <= 0 {
+		return
+	}
+	size, bits := cap(item), uint(0)
+	for size != 0 {
+		size >>= 1
+		bits++
+	}
+	size = 1 << (bits - 1)
+	if size > 0 && float64(cap(item))/float64(size) <= 1.2 {
+		if slab, ok := slabs[size]; ok {
+			atomic.AddInt64(&(slab.put), 1)
+			select {
+			case slab.queue <- item:
+			default:
+				atomic.AddInt64(&(slab.lost), 1)
+			}
+		} else {
+			atomic.AddInt64(&(slabs[0].put), 1)
+			atomic.AddInt64(&(slabs[0].lost), int64(cap(item)))
+		}
+	} else {
+		atomic.AddInt64(&(slabs[0].put), 1)
+		atomic.AddInt64(&(slabs[0].lost), int64(cap(item)))
+	}
+}